Hustle and Focus Plays a HUGE role in getting plays right, along with specific entangables that are described in the NFHS Officials Manual. Here are a few tips that should help you improve your court coverage abilities:

Hustle Into Position During Transition/Change of Possession
Obtain Dependable Position/Open Look
Make Proper Adjustments To Maintain Dependable Position/Open Look
ALL OFFICIALS are responsible for refereeing rebound action
Referee the ENTIRE PLAY until there is a Change of Possession